1. Field of the Invention
This invention relates to an automatic adjuster for a shoe-drum brake, primarily for use on a motor vehicle, the adjuster incorporating a strut of variable length which includes a pair of threadedly interengaged parts, relative rotation between which causes the strut length to vary so as to effect adjustment of the retracted positions of one or more brake shoes with which the strut is operatively associated in use.
2. Description of the Prior Art
In some adjusters of this kind, it is possible for opposed surfaces of the strut parts to be forced into engagement by the screw action of the parts, resulting in jamming of the adjuster when said parts are at an extremity of their adjusting travel, which can prevent subsequent automatic operation of the adjuster. This can happen, for example, when the adjuster is retracted manually during servicing of the brake in order to facilitate removal of the brake drum. When this happens, there is a risk of neglecting to free the jammed adjuster parts during re-assembly of the brake and the brake consequently not achieving an optimum operational condition.